Contributions to cooperative dIversity in multiple access UWB systems
type: Dataset
contact point: Organization
  fn: CCSD
keyword: cooperative-diversity
keyword: ulb
keyword: theses
keyword: virtual-mimo
keyword: spiotherengineering-sciences-physicsother
keyword: infoeu-reposemanticsdoctoralthesis
keyword: antennas-selection
keyword: selection-dantennes
keyword: uwb
keyword: rake-receiver
keyword: recepteur-rake
keyword: diversite-cooperative
keyword: mimo-virtuel
landing page: https://theses.hal.science/tel-00954499
description: This work focuses on the ultra wideband (UWB) transmission in wireless networks. Spatial diversity is introduced by the use of multiple-input multiple-output (MIMO) system as an effective technique to overcome multipath fading in wireless communications. But the integration of multiple antennas at the transmitter or receiver is often costly. As an alternative, we propose to use the cooperative diversity that provides spatial diversity gains by exploiting the traditional MIMO techniques without the need for multiple antennas. The objective is to introduce cooperative diversity to UWB transmission systems. We consider two multiple access techniques with different modulation schemes (time hopping pulse position modulation TH-PPM and direct sequence binary Phase Shift Keying DS-BPSK) with the cooperation protocol decode-and-forward (DF). We use the Rake receiver to exploit multipath diversity and analyze the decision variable statistics at the output of the receiver. We present simulation results of the BER performance of the proposed system under different UWB channel given the IEEE 802.15.4a standard. Our results show that the cooperation with the relay significantly improves the performance of UWB transmission, and that the diversity gain increases with the number of relays. In the presence of MAI, the overall system performance degrades significantly, but the benefit of cooperation is still moderately effective. The performance in this case is limited in terms of attainable diversity that the source-relay link becomes worse when MAI is present. That is why we propose to use antenna selection at the relay receiver in order to improve the reliability of the source-relay link. This solution is shown to improve the performance by exploiting the diversity of the available antennas at the relay, while using a single Radio Frequency (RF) chains. This leads to reduced cost and complexity.
identifier: NNT: 2013VALE0036
issued: 2026-05-06T04:15:21.847388
language: en
modified: 2026-05-06T04:15:21.847392

test_moissonnage_selune
type: Agent

Contributions to cooperative dIversity in multiple access UWB systems
type: Distribution
access URL: https://theses.hal.science/tel-00954499
format: HTML
issued: 2026-05-06T04:15:21.870991
modified: 2026-05-06T04:15:21.833606